China coronavirus cases fall, but more imported from abroad

Washington, May 12: The US Federal Bureau of Investigation and cybersecurity experts believe Chinese hackers are trying to steal research on developing a vaccine against coronavirus, two newspapers reported Monday.

The FBI and Department of Homeland Security are planning to release a warning about the Chinese hacking as governments and private firms race to develop a vaccine for COVID-19, the Wall Street Journal and New York Times reported.

The hackers are also targeting information and intellectual property on treatments and testing for COVID-19.

US officials alleged that the hackers are linked to the Chinese government, the reports say.

The official warning could come within days.

In Beijing Foreign Affairs ministry spokesman Zhao Lijian rejected the allegation, saying China firmly opposes all cyber attacks.

"We are leading the world in COVID-19 treatment and vaccine research. It is immoral to target China with rumors and slanders in the absence of any evidence," Zhao said.

Asked about the reports, President Donald Trump did not confirm them, but said: "What else is new with China? What else is new? Tell me. I'm not happy with China."

"We're watching it very closely," he added.

A US warning would add to a series of alerts and reports accusing government-backed hackers in Iran, North Korea, Russia and China of malicious activity related to the pandemic, from pumping out false news to targeting workers and scientists.

The New York Times said it could be a prelude to officially-sanctioned counterattacks by US agencies involved in cyber warfare, including the Pentagon's Cyber Command and the National Security Agency.

Last week in a joint message Britain and the United States warned of a rise in cyber attacks against health professionals involved in the coronavirus response by organised criminals "often linked with other state actors."

Britain's National Cyber Security Centre and the US Cybersecurity and Infrastructure Security Agency said they had detected large-scale "password spraying" tactics -- hackers trying to access accounts through commonly used passwords -- aimed at healthcare bodies and medical research organisations.

London, May 20: The current physical distancing guidelines of 6 feet may be insufficient to prevent COVID-19 transmission, according to a study which says a mild cough in low wind speeds can propel saliva droplets by as much as 18 feet.

Researchers, including those from the University of Nicosia in Cyprus, said a good baseline for studying the airborne transmission of viruses, like the one behind the COVID-19 pandemic, is a deeper understanding of how particles travel through the air when people cough.

In the study, published in the journal Physics of Fluids, they said even with a slight breeze of about four kilometres per hour (kph), saliva travels 18 feet in 5 seconds.

"The droplet cloud will affect both adults and children of different heights," said study co-author Dimitris Drikakis from the University of Nicosia.

According to the scientists, shorter adults and children could be at higher risk if they are located within the trajectory of the saliva droplets.

They said saliva is a complex fluid, which travels suspended in a bulk of surrounding air released by a cough, adding that many factors affect how saliva droplets travel in the air.

These factors, the study noted, include the size and number of droplets, how they interact with one another and the surrounding air as they disperse and evaporate, how heat and mass are transferred, and the humidity and temperature of the surrounding air.

In the study, the scientists created a computer simulation to examine the state of every saliva droplet moving through the air in front of a coughing person.

The model considered the effects of humidity, dispersion force, interactions of molecules of saliva and air, and how the droplets change from liquid to vapour and evaporate, along with a grid representing the space in front of a coughing person.

Each grid, the scientists said, holds information about variables like pressure, fluid velocity, temperature, droplet mass, and droplet position.

The study analysed the fates of nearly 1,008 simulated saliva droplets, and solved as many as 3.7 million equations.

"The purpose of the mathematical modelling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves," explained Talib Dbouk, another co-author of the study.

However, the researchers added that further studies are needed to determine the effect of ground surface temperature on the behaviour of saliva in air.

They also believe that indoor environments, especially ones with air conditioning, may significantly affect the particle movement through air.

This work is important since it concerns safety distance guidelines, and advances the understanding of the transmission of airborne diseases, Drikakis said.

Geneva, Jul 11: The World Health Organization said Friday that it is still possible to bring coronavirus outbreaks under control, even though case numbers have more than doubled in the past six weeks.

WHO chief Tedros Adhanom Ghebreyesus said the examples of Italy, Spain, South Korea and India's biggest slum showed that however bad a outbreak was, the virus could still be reined in through aggressive action.

"In the last six weeks cases have more than doubled," Tedros told a virtual press conference in Geneva.

However, "there are many examples from around the world that have shown that even if the outbreak is very intense, it can still be brought back under control," said Tedros.

"And some of these examples are Italy, Spain and South Korea, and even in Dharavi -- a densely packed area in the megacity of Mumbai -- a strong focus on community engagement and the basics of testing, tracing, isolating and treating all those that are sick is key to breaking the chains of transmission and suppressing the virus."

The novel coronavirus has killed at least 555,000 people worldwide since the outbreak emerged in China last December, according to a tally from official sources compiled by AFP on Friday.

Nearly 12.3 million cases have been registered in 196 countries and territories.

"Across all walks of life, we are all being tested to the limit," Tedros said, "from countries where there is exponential growth, to places that are loosening restrictions and now starting to see cases rise.

"Only aggressive action combined with national unity and global solidarity can turn this pandemic around."